Survival and mortality pattern among Swedish smelter workers

Abstract

The study analyses work history and mortality data for 3919 male workers first employed during 1928-66 at Rönnskärsverken, a copper smelter in north-east Sweden. 99% of the workers were traced from employment records and central population registers. By means of standarized mortality ratios and life-table analysis comparisons were made with both the general and local populations. For all causes excess mortality is 18% relative to the general population. This can be ascribed to tumours and circulatory diseases, for which excess figures are 39 and 32% respectively. For tumours, the excess mortality is mainly due to lung cancer for which the risk is trebled relative to the general population and 5-fold relative to local populations. For circulatory diseases, the excess figure is mainly accounted for by cerebrovascular disease with an elevated risk of 60-70%. The probable remaining life-time from 50 years is 2 years shorter than for Swedish men in the 60's. Internal comparisons were made to analyse the importance of latency, exposure, calendar time and place of work. A dose-response analysis clearly indicates that the roasters and arsenic departments are risk places for the development of cancer, especially lung cancer. A 50-year old worker who has been exposed to the roasters for more than 5 years, has a probable remaining life-time which is almost 3 years shorter than the average Rönnskär employee and almost 5 years shorter than the average Swedish male. Case-control studies aimed at exploring exposure associated with stomach cancer and cerebrovascular mortality are under way.